SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 ----------------------- FORM 8-K/A CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of event reported): DECEMBER 20, 1999 GENOME THERAPEUTICS CORP. (Exact name of registrant as specified in its charter) MASSACHUSETTS 0-10824 04-2297484 (State or other jurisdiction (Commission File (IRS Employer of incorporation) Number) Identification No.) 100 BEAVER STREET, WALTHAM, MASSACHUSETTS 02453 (Address of principal executive offices and zip code) Registrant's telephone number, including area code: (781) 398-2300 ITEM 5. On December 20, 1999, Genome Therapeutics Corporation entered into a collaboration and license agreement with American Home Products Corporation. This current report on Form 8-K is filed solely to file such agreement to disclose portions of the agreement that were previously redacted. ITEM 7. FINANCIAL STATEMENTS, PRO FORMA FINANCIAL INFORMATION AND EXHIBITS. (a) Financial Statements of Business Acquired. Not applicable. (b) PRO FORMA Financial Information. Not applicable. (c) Exhibits 10.1* Collaboration and License Agreement between Genome Therapeutics Corporation, and American Home Products Corporation dated as of December 20, 1999. Filed herewith. * Certain confidential material contained in the document has been omitted and filed separately with the SEC pursuant to Rule 24b-2 of the Securities Exchange Act of 1934. 2 SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. April 10, 2000 GENOME THERAPEUTICS CORP. By: /S/ PHILIP V HOLBERTON --------------------------------- Philip V. Holberton Chief Financial Officer 3 EXHIBIT INDEX 10.1* Collaboration and License Agreement between Genome Therapeutics Corporation, and American Home Products Corporation dated as of December 20, 1999. Filed herewith. * Certain confidential material contained in the document has been omitted and filed separately with the SEC pursuant to Rule 24b-2 of the Securities Exchange Act of 1934. 4